Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
MIME-Version: 1.0
References: <1629876516-16513-1-git-send-email-shengjiu.wang@nxp.com>
 <1629876516-16513-2-git-send-email-shengjiu.wang@nxp.com> <20210901162238.GB1033512@p14s>
In-Reply-To: <20210901162238.GB1033512@p14s>
From:   Shengjiu Wang <shengjiu.wang@gmail.com>
Date:   Thu, 2 Sep 2021 10:54:24 +0800
Message-ID: <CAA+D8ANexj6YHoG4+hEdiCd9Mq1fjm7L7fp8q-tPZbD_fdU=iA@mail.gmail.com>
Subject: Re: [PATCH v2 2/2] remoteproc: imx_dsp_rproc: add remoteproc driver
 for dsp on i.MX
To:     Mathieu Poirier <mathieu.poirier@linaro.org>
Cc:     Shengjiu Wang <shengjiu.wang@nxp.com>,
        Ohad Ben Cohen <ohad@wizery.com>, bjorn.andersson@linaro.org,
        Rob Herring <robh+dt@kernel.org>,
        Shawn Guo <shawnguo@kernel.org>,
        Sascha Hauer <s.hauer@pengutronix.de>,
        Sascha Hauer <kernel@pengutronix.de>,
        Fabio Estevam <festevam@gmail.com>,
        NXP Linux Team <linux-imx@nxp.com>,
        linux-remoteproc@vger.kernel.org,
        "open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS" 
        <devicetree@vger.kernel.org>,
        "moderated list:ARM/FREESCALE IMX / MXC ARM ARCHITECTURE" 
        <linux-arm-kernel@lists.infradead.org>,
        linux-kernel <linux-kernel@vger.kernel.org>
Content-Type: text/plain; charset="UTF-8"
Precedence: bulk

On Thu, Sep 2, 2021 at 12:22 AM Mathieu Poirier
<mathieu.poirier@linaro.org> wrote:
>
> On Wed, Aug 25, 2021 at 03:28:36PM +0800, Shengjiu Wang wrote:
> > Provide a basic driver to control DSP processor found on NXP i.MX8QM,
> > i.MX8QXP, i.MX8MP and i.MX8ULP.
> >
> > Currently it is able to resolve addresses between DSP and main CPU,
> > start and stop the processor, suspend and resume.
> >
> > The communication between DSP and main CPU is based on mailbox, there
> > are three mailbox channels (tx, rx, rxdb).
> >
> > This driver was tested on NXP i.MX8QM, i.MX8QXP, i.MX8MP and i.MX8ULP.
> >
> > Signed-off-by: Shengjiu Wang <shengjiu.wang@nxp.com>
> > ---
> > changes in v2:
> > - change syscon to fsl,dsp-ctrl
> >
> >  drivers/remoteproc/Kconfig         |   11 +
> >  drivers/remoteproc/Makefile        |    1 +
> >  drivers/remoteproc/imx_dsp_rproc.c | 1078 ++++++++++++++++++++++++++++
> >  3 files changed, 1090 insertions(+)
> >  create mode 100644 drivers/remoteproc/imx_dsp_rproc.c
> >
> > diff --git a/drivers/remoteproc/Kconfig b/drivers/remoteproc/Kconfig
> > index 9a6eedc3994a..890a14e6f3f9 100644
> > --- a/drivers/remoteproc/Kconfig
> > +++ b/drivers/remoteproc/Kconfig
> > @@ -34,6 +34,17 @@ config IMX_REMOTEPROC
> >
> >         It's safe to say N here.
> >
> > +config IMX_DSP_REMOTEPROC
> > +     tristate "i.MX DSP remoteproc support"
> > +     depends on ARCH_MXC
> > +     depends on HAVE_ARM_SMCCC
> > +     select MAILBOX
> > +     help
> > +       Say y here to support iMX's DSP remote processors via the remote
> > +       processor framework.
> > +
> > +       It's safe to say N here.
> > +
> >  config INGENIC_VPU_RPROC
> >       tristate "Ingenic JZ47xx VPU remoteproc support"
> >       depends on MIPS || COMPILE_TEST
> > diff --git a/drivers/remoteproc/Makefile b/drivers/remoteproc/Makefile
> > index bb26c9e4ef9c..37d5cb1c04bf 100644
> > --- a/drivers/remoteproc/Makefile
> > +++ b/drivers/remoteproc/Makefile
> > @@ -12,6 +12,7 @@ remoteproc-y                                += remoteproc_virtio.o
> >  remoteproc-y                         += remoteproc_elf_loader.o
> >  obj-$(CONFIG_REMOTEPROC_CDEV)                += remoteproc_cdev.o
> >  obj-$(CONFIG_IMX_REMOTEPROC)         += imx_rproc.o
> > +obj-$(CONFIG_IMX_DSP_REMOTEPROC)     += imx_dsp_rproc.o
> >  obj-$(CONFIG_INGENIC_VPU_RPROC)              += ingenic_rproc.o
> >  obj-$(CONFIG_MTK_SCP)                        += mtk_scp.o mtk_scp_ipi.o
> >  obj-$(CONFIG_OMAP_REMOTEPROC)                += omap_remoteproc.o
> > diff --git a/drivers/remoteproc/imx_dsp_rproc.c b/drivers/remoteproc/imx_dsp_rproc.c
> > new file mode 100644
> > index 000000000000..ce0596694122
> > --- /dev/null
> > +++ b/drivers/remoteproc/imx_dsp_rproc.c
> > @@ -0,0 +1,1078 @@
> > +// SPDX-License-Identifier: GPL-2.0-only
> > +// Copyright 2021 NXP
> > +
> > +#include <linux/clk.h>
> > +#include <linux/err.h>
> > +#include <linux/interrupt.h>
> > +#include <linux/kernel.h>
> > +#include <linux/mailbox_client.h>
> > +#include <linux/mfd/syscon.h>
> > +#include <linux/module.h>
> > +#include <linux/of_address.h>
> > +#include <linux/of_reserved_mem.h>
> > +#include <linux/of_device.h>
> > +#include <linux/platform_device.h>
> > +#include <linux/pm_domain.h>
> > +#include <linux/regmap.h>
> > +#include <linux/remoteproc.h>
> > +#include <linux/slab.h>
> > +#include <linux/pm_runtime.h>
> > +#include <linux/workqueue.h>
> > +#include <linux/firmware/imx/sci.h>
> > +#include <dt-bindings/firmware/imx/rsrc.h>
> > +#include <linux/arm-smccc.h>
> > +
> > +#include "remoteproc_internal.h"
> > +#include "remoteproc_elf_helpers.h"
> > +
> > +enum imx_dsp_rp_mbox_messages {
> > +     RP_MBOX_SUSPEND_SYSTEM  = 0xFF11,
> > +     RP_MBOX_SUSPEND_ACK     = 0xFF12,
> > +     RP_MBOX_RESUME_SYSTEM   = 0xFF13,
> > +     RP_MBOX_RESUME_ACK      = 0xFF14,
> > +};
> > +
> > +#define DSP_RPROC_CLK_MAX 32
> > +
> > +#define REMOTE_IS_READY                      BIT(0)
> > +#define REMOTE_READY_WAIT_MAX_RETRIES        500
> > +
> > +/* att flags */
> > +/* DSP own area. Can be mapped at probe */
> > +#define ATT_OWN              BIT(31)
> > +#define ATT_IRAM     BIT(30)
> > +
> > +/* i.MX8MP */
> > +/* DAP registers */
> > +#define IMX8M_DAP_DEBUG                0x28800000
> > +#define IMX8M_DAP_DEBUG_SIZE           (64 * 1024)
> > +#define IMX8M_DAP_PWRCTL               (0x4000 + 0x3020)
> > +#define IMX8M_PWRCTL_CORERESET         BIT(16)
> > +
> > +/* DSP audio mix registers */
> > +#define IMX8M_AudioDSP_REG0   0x100
> > +#define IMX8M_AudioDSP_REG1   0x104
> > +#define IMX8M_AudioDSP_REG2   0x108
> > +#define IMX8M_AudioDSP_REG3   0x10c
> > +
> > +#define IMX8M_AudioDSP_REG2_RUNSTALL  BIT(5)
> > +#define IMX8M_AudioDSP_REG2_PWAITMODE BIT(1)
> > +
> > +/* i.MX8ULP */
> > +#define IMX8ULP_SIM_LPAV_REG_SYSCTRL0       0x8
> > +#define IMX8ULP_SYSCTRL0_DSP_DBG_RST        BIT(25)
> > +#define IMX8ULP_SYSCTRL0_DSP_PLAT_CLK_EN    BIT(19)
> > +#define IMX8ULP_SYSCTRL0_DSP_PBCLK_EN       BIT(18)
> > +#define IMX8ULP_SYSCTRL0_DSP_CLK_EN         BIT(17)
> > +#define IMX8ULP_SYSCTRL0_DSP_RST            BIT(16)
> > +#define IMX8ULP_SYSCTRL0_DSP_OCD_HALT       BIT(14)
> > +#define IMX8ULP_SYSCTRL0_DSP_STALL          BIT(13)
> > +
> > +#define IMX8ULP_SIP_HIFI_XRDC         0xc200000e
> > +
> > +/* address translation table */
> > +struct imx_dsp_rproc_att {
> > +     u32 da; /* device address (From Cortex M4 view)*/
> > +     u32 sa; /* system bus address */
> > +     u32 size; /* size of reg range */
> > +     int flags;
> > +};
> > +
> > +/* Remote core start/stop method */
> > +enum imx_dsp_rproc_method {
> > +     /* Through syscon regmap */
> > +     IMX_DSP_MMIO,
> > +     IMX_DSP_SCU_API,
> > +};
> > +
> > +struct imx_dsp_rproc {
> > +     struct device                   *dev;
> > +     struct regmap                   *regmap;
> > +     struct rproc                    *rproc;
> > +     const struct imx_dsp_rproc_dcfg *dcfg;
> > +     struct clk                      *clks[DSP_RPROC_CLK_MAX];
> > +     struct mbox_client              cl;
> > +     struct mbox_client              cl_rxdb;
> > +     struct mbox_chan                *tx_ch;
> > +     struct mbox_chan                *rx_ch;
> > +     struct mbox_chan                *rxdb_ch;
> > +     struct device                   **pd_dev;
> > +     struct device_link              **pd_dev_link;
> > +     struct imx_sc_ipc               *ipc_handle;
> > +     struct work_struct              rproc_work;
> > +     struct workqueue_struct         *workqueue;
> > +     struct completion               pm_comp;
> > +     spinlock_t                      mbox_lock;    /* lock for mbox */
> > +     int                             num_domains;
> > +     u32                             flags;
> > +};
> > +
> > +struct imx_dsp_rproc_dcfg {
> > +     u32                             src_reg;
> > +     u32                             src_mask;
> > +     u32                             src_start;
> > +     u32                             src_stop;
> > +     const struct imx_dsp_rproc_att  *att;
> > +     size_t                          att_size;
> > +     enum imx_dsp_rproc_method       method;
> > +     int (*reset)(struct imx_dsp_rproc *priv);
> > +};
> > +
> > +static const struct imx_dsp_rproc_att imx_dsp_rproc_att_imx8qm[] = {
> > +     /* dev addr , sys addr  , size      , flags */
> > +     { 0x596e8000, 0x556e8000, 0x00008000, ATT_OWN },
> > +     { 0x596f0000, 0x556f0000, 0x00008000, ATT_OWN },
> > +     { 0x596f8000, 0x556f8000, 0x00000800, ATT_OWN | ATT_IRAM},
> > +     { 0x55700000, 0x55700000, 0x00070000, ATT_OWN },
> > +     /* DDR (Data) */
> > +     { 0x80000000, 0x80000000, 0x60000000, 0},
> > +};
> > +
> > +static const struct imx_dsp_rproc_att imx_dsp_rproc_att_imx8qxp[] = {
> > +     /* dev addr , sys addr  , size      , flags */
> > +     { 0x596e8000, 0x596e8000, 0x00008000, ATT_OWN },
> > +     { 0x596f0000, 0x596f0000, 0x00008000, ATT_OWN },
> > +     { 0x596f8000, 0x596f8000, 0x00000800, ATT_OWN | ATT_IRAM},
> > +     { 0x59700000, 0x59700000, 0x00070000, ATT_OWN },
> > +     /* DDR (Data) */
> > +     { 0x80000000, 0x80000000, 0x60000000, 0},
> > +};
> > +
> > +static const struct imx_dsp_rproc_att imx_dsp_rproc_att_imx8mp[] = {
> > +     /* dev addr , sys addr  , size      , flags */
> > +     { 0x3b6e8000, 0x3b6e8000, 0x00008000, ATT_OWN },
> > +     { 0x3b6f0000, 0x3b6f0000, 0x00008000, ATT_OWN },
> > +     { 0x3b6f8000, 0x3b6f8000, 0x00000800, ATT_OWN | ATT_IRAM},
> > +     { 0x3b700000, 0x3b700000, 0x00040000, ATT_OWN },
> > +     /* DDR (Data) */
> > +     { 0x40000000, 0x40000000, 0x80000000, 0},
> > +};
> > +
> > +static const struct imx_dsp_rproc_att imx_dsp_rproc_att_imx8ulp[] = {
> > +     /* dev addr , sys addr  , size      , flags */
> > +     { 0x21170000, 0x21170000, 0x00010000, ATT_OWN | ATT_IRAM},
> > +     { 0x21180000, 0x21180000, 0x00010000, ATT_OWN },
> > +     /* DDR (Data) */
> > +     { 0x0c000000, 0x80000000, 0x10000000, 0},
> > +     { 0x30000000, 0x90000000, 0x10000000, 0},
> > +};
> > +
> > +static int imx8mp_dsp_reset(struct imx_dsp_rproc *priv)
> > +{
> > +     void __iomem *dap = ioremap_wc(IMX8M_DAP_DEBUG, IMX8M_DAP_DEBUG_SIZE);
> > +     int pwrctl;
> > +
> > +     /* put DSP into reset and stall */
> > +     pwrctl = readl(dap + IMX8M_DAP_PWRCTL);
> > +     pwrctl |= IMX8M_PWRCTL_CORERESET;
> > +     writel(pwrctl, dap + IMX8M_DAP_PWRCTL);
> > +
> > +     /* keep reset asserted for 10 cycles */
> > +     usleep_range(1, 2);
> > +
> > +     regmap_update_bits(priv->regmap, IMX8M_AudioDSP_REG2,
> > +                        IMX8M_AudioDSP_REG2_RUNSTALL,
> > +                        IMX8M_AudioDSP_REG2_RUNSTALL);
> > +
> > +     /* take the DSP out of reset and keep stalled for FW loading */
> > +     pwrctl = readl(dap + IMX8M_DAP_PWRCTL);
> > +     pwrctl &= ~IMX8M_PWRCTL_CORERESET;
> > +     writel(pwrctl, dap + IMX8M_DAP_PWRCTL);
> > +
> > +     iounmap(dap);
> > +     return 0;
> > +}
> > +
> > +static int imx8ulp_dsp_reset(struct imx_dsp_rproc *priv)
> > +{
> > +     struct arm_smccc_res res;
> > +
> > +     regmap_update_bits(priv->regmap, IMX8ULP_SIM_LPAV_REG_SYSCTRL0,
> > +                        IMX8ULP_SYSCTRL0_DSP_RST, IMX8ULP_SYSCTRL0_DSP_RST);
> > +     regmap_update_bits(priv->regmap, IMX8ULP_SIM_LPAV_REG_SYSCTRL0,
> > +                        IMX8ULP_SYSCTRL0_DSP_STALL,
> > +                        IMX8ULP_SYSCTRL0_DSP_STALL);
> > +
> > +     arm_smccc_smc(IMX8ULP_SIP_HIFI_XRDC, 0, 0, 0, 0, 0, 0, 0, &res);
> > +
> > +     regmap_update_bits(priv->regmap, IMX8ULP_SIM_LPAV_REG_SYSCTRL0,
> > +                        IMX8ULP_SYSCTRL0_DSP_RST, 0);
> > +     regmap_update_bits(priv->regmap, IMX8ULP_SIM_LPAV_REG_SYSCTRL0,
> > +                        IMX8ULP_SYSCTRL0_DSP_DBG_RST, 0);
> > +
> > +     return 0;
> > +}
> > +
> > +static const struct imx_dsp_rproc_dcfg imx_dsp_rproc_cfg_imx8mp = {
> > +     .src_reg        = IMX8M_AudioDSP_REG2,
> > +     .src_mask       = IMX8M_AudioDSP_REG2_RUNSTALL,
> > +     .src_start      = 0,
> > +     .src_stop       = IMX8M_AudioDSP_REG2_RUNSTALL,
> > +     .att            = imx_dsp_rproc_att_imx8mp,
> > +     .att_size       = ARRAY_SIZE(imx_dsp_rproc_att_imx8mp),
> > +     .method         = IMX_DSP_MMIO,
> > +     .reset          = imx8mp_dsp_reset,
> > +};
> > +
> > +static const struct imx_dsp_rproc_dcfg imx_dsp_rproc_cfg_imx8ulp = {
> > +     .src_reg        = IMX8ULP_SIM_LPAV_REG_SYSCTRL0,
> > +     .src_mask       = IMX8ULP_SYSCTRL0_DSP_STALL,
> > +     .src_start      = 0,
> > +     .src_stop       = IMX8ULP_SYSCTRL0_DSP_STALL,
> > +     .att            = imx_dsp_rproc_att_imx8ulp,
> > +     .att_size       = ARRAY_SIZE(imx_dsp_rproc_att_imx8ulp),
> > +     .method         = IMX_DSP_MMIO,
> > +     .reset          = imx8ulp_dsp_reset,
> > +};
> > +
> > +static const struct imx_dsp_rproc_dcfg imx_dsp_rproc_cfg_imx8qxp = {
> > +     .att            = imx_dsp_rproc_att_imx8qxp,
> > +     .att_size       = ARRAY_SIZE(imx_dsp_rproc_att_imx8qxp),
> > +     .method         = IMX_DSP_SCU_API,
> > +};
> > +
> > +static const struct imx_dsp_rproc_dcfg imx_dsp_rproc_cfg_imx8qm = {
> > +     .att            = imx_dsp_rproc_att_imx8qm,
> > +     .att_size       = ARRAY_SIZE(imx_dsp_rproc_att_imx8qm),
> > +     .method         = IMX_DSP_SCU_API,
> > +};
> > +
> > +static int imx_dsp_rproc_ready(struct rproc *rproc)
> > +{
> > +     struct imx_dsp_rproc *priv = rproc->priv;
> > +     int i;
> > +
> > +     if (!priv->rxdb_ch)
> > +             return 0;
> > +
> > +     for (i = 0; i < REMOTE_READY_WAIT_MAX_RETRIES; i++) {
> > +             if (priv->flags & REMOTE_IS_READY)
> > +                     return 0;
> > +             usleep_range(100, 200);
> > +     }
> > +
> > +     return -ETIMEDOUT;
> > +}
> > +
> > +static int imx_dsp_rproc_start(struct rproc *rproc)
> > +{
> > +     struct imx_dsp_rproc *priv = rproc->priv;
> > +     const struct imx_dsp_rproc_dcfg *dcfg = priv->dcfg;
> > +     struct device *dev = priv->dev;
> > +     int ret;
> > +
> > +     switch (dcfg->method) {
> > +     case IMX_DSP_MMIO:
> > +             ret = regmap_update_bits(priv->regmap,
> > +                                      dcfg->src_reg,
> > +                                      dcfg->src_mask,
> > +                                      dcfg->src_start);
> > +             break;
> > +     case IMX_DSP_SCU_API:
> > +             ret = imx_sc_pm_cpu_start(priv->ipc_handle,
> > +                                       IMX_SC_R_DSP,
> > +                                       true,
> > +                                       rproc->bootaddr);
> > +             break;
> > +     default:
> > +             return -EOPNOTSUPP;
> > +     }
> > +
> > +     if (ret)
> > +             dev_err(dev, "Failed to enable remote core!\n");
> > +     else
> > +             ret = imx_dsp_rproc_ready(rproc);
> > +
> > +     return ret;
> > +}
> > +
> > +static int imx_dsp_rproc_stop(struct rproc *rproc)
> > +{
> > +     struct imx_dsp_rproc *priv = rproc->priv;
> > +     const struct imx_dsp_rproc_dcfg *dcfg = priv->dcfg;
> > +     struct device *dev = priv->dev;
> > +     int ret = 0;
> > +
> > +     if (rproc->state == RPROC_CRASHED) {
> > +             priv->flags &= ~REMOTE_IS_READY;
> > +             return 0;
> > +     }
> > +
> > +     switch (dcfg->method) {
> > +     case IMX_DSP_MMIO:
> > +             ret = regmap_update_bits(priv->regmap, dcfg->src_reg, dcfg->src_mask,
> > +                                      dcfg->src_stop);
> > +             break;
> > +     case IMX_DSP_SCU_API:
> > +             ret = imx_sc_pm_cpu_start(priv->ipc_handle,
> > +                                       IMX_SC_R_DSP,
> > +                                       false,
> > +                                       rproc->bootaddr);
> > +             break;
> > +     default:
> > +             return -EOPNOTSUPP;
> > +     }
> > +
> > +     if (ret)
> > +             dev_err(dev, "Failed to stop remote core\n");
> > +     else
> > +             priv->flags &= ~REMOTE_IS_READY;
> > +
> > +     return ret;
> > +}
> > +
> > +static int imx_dsp_rproc_sys_to_da(struct imx_dsp_rproc *priv, u64 sys,
> > +                                size_t len, u64 *da)
> > +{
> > +     const struct imx_dsp_rproc_dcfg *dcfg = priv->dcfg;
> > +     int i;
> > +
> > +     /* parse address translation table */
> > +     for (i = 0; i < dcfg->att_size; i++) {
> > +             const struct imx_dsp_rproc_att *att = &dcfg->att[i];
> > +
> > +             if (sys >= att->sa && sys + len <= att->sa + att->size) {
> > +                     unsigned int offset = sys - att->sa;
> > +
> > +                     *da = att->da + offset;
> > +                     return 0;
> > +             }
> > +     }
> > +
> > +     return -ENOENT;
> > +}
> > +
> > +static void imx_dsp_rproc_vq_work(struct work_struct *work)
> > +{
> > +     struct imx_dsp_rproc *priv = container_of(work, struct imx_dsp_rproc,
> > +                                               rproc_work);
> > +
> > +     rproc_vq_interrupt(priv->rproc, 0);
> > +     rproc_vq_interrupt(priv->rproc, 1);
> > +}
> > +
> > +static void imx_dsp_rproc_rx_callback(struct mbox_client *cl, void *data)
> > +{
> > +     struct rproc *rproc = dev_get_drvdata(cl->dev);
> > +     struct imx_dsp_rproc *priv = rproc->priv;
> > +     u32 message = (u32)(*(u32 *)data);
> > +
> > +     dev_dbg(priv->dev, "mbox msg: 0x%x\n", message);
> > +
> > +     switch (message) {
> > +     case RP_MBOX_SUSPEND_ACK:
> > +             complete(&priv->pm_comp);
> > +             break;
> > +     case RP_MBOX_RESUME_ACK:
> > +             complete(&priv->pm_comp);
> > +             break;
> > +     default:
> > +             queue_work(priv->workqueue, &priv->rproc_work);
> > +             break;
> > +     }
> > +}
> > +
> > +static void imx_dsp_rproc_rxdb_callback(struct mbox_client *cl, void *msg)
> > +{
> > +     struct rproc *rproc = dev_get_drvdata(cl->dev);
> > +     struct imx_dsp_rproc *priv = rproc->priv;
> > +     unsigned long flags;
> > +
> > +     spin_lock_irqsave(&priv->mbox_lock, flags);
> > +     priv->flags |= REMOTE_IS_READY;
> > +     spin_unlock_irqrestore(&priv->mbox_lock, flags);
> > +}
> > +
> > +static int imx_dsp_rproc_mbox_init(struct imx_dsp_rproc *priv)
> > +{
> > +     struct device *dev = priv->dev;
> > +     struct mbox_client *cl;
> > +     int ret;
> > +
> > +     if (!of_get_property(dev->of_node, "mbox-names", NULL))
> > +             return 0;
> > +
> > +     spin_lock_init(&priv->mbox_lock);
> > +
> > +     cl = &priv->cl;
> > +     cl->dev = dev;
> > +     cl->tx_block = true;
> > +     cl->tx_tout = 100;
> > +     cl->knows_txdone = false;
> > +     cl->rx_callback = imx_dsp_rproc_rx_callback;
> > +
> > +     priv->tx_ch = mbox_request_channel_byname(cl, "tx");
> > +     if (IS_ERR(priv->tx_ch)) {
> > +             ret = PTR_ERR(priv->tx_ch);
> > +             dev_dbg(cl->dev, "failed to request tx mailbox channel: %d\n",
> > +                     ret);
> > +             goto err_out;
> > +     }
> > +
> > +     priv->rx_ch = mbox_request_channel_byname(cl, "rx");
> > +     if (IS_ERR(priv->rx_ch)) {
> > +             ret = PTR_ERR(priv->rx_ch);
> > +             dev_dbg(cl->dev, "failed to request rx mailbox channel: %d\n",
> > +                     ret);
> > +             goto err_out;
> > +     }
> > +
> > +     cl = &priv->cl_rxdb;
> > +     cl->dev = dev;
> > +     cl->rx_callback = imx_dsp_rproc_rxdb_callback;
> > +
> > +     /*
> > +      * RX door bell is used to receive the ready signal from remote
> > +      * after the partition reset of A core.
> > +      */
> > +     priv->rxdb_ch = mbox_request_channel_byname(cl, "rxdb");
> > +     if (IS_ERR(priv->rxdb_ch)) {
> > +             ret = PTR_ERR(priv->rxdb_ch);
> > +             dev_dbg(cl->dev, "failed to request mbox chan rxdb, ret %d\n",
> > +                     ret);
> > +             goto err_out;
> > +     }
> > +
> > +     return 0;
> > +
> > +err_out:
> > +     if (!IS_ERR(priv->tx_ch))
> > +             mbox_free_channel(priv->tx_ch);
> > +     if (!IS_ERR(priv->rx_ch))
> > +             mbox_free_channel(priv->rx_ch);
> > +     if (!IS_ERR(priv->rxdb_ch))
> > +             mbox_free_channel(priv->rxdb_ch);
> > +
> > +     return ret;
> > +}
> > +
> > +static void imx_dsp_rproc_free_mbox(struct imx_dsp_rproc *priv)
> > +{
> > +     mbox_free_channel(priv->tx_ch);
> > +     mbox_free_channel(priv->rx_ch);
> > +     mbox_free_channel(priv->rxdb_ch);
> > +}
> > +
> > +static int imx_dsp_rproc_add_carveout(struct imx_dsp_rproc *priv)
> > +{
> > +     const struct imx_dsp_rproc_dcfg *dcfg = priv->dcfg;
> > +     struct rproc *rproc = priv->rproc;
> > +     struct device *dev = priv->dev;
> > +     struct device_node *np = dev->of_node;
> > +     struct of_phandle_iterator it;
> > +     struct rproc_mem_entry *mem;
> > +     struct reserved_mem *rmem;
> > +     void __iomem *cpu_addr;
> > +     int a;
> > +     u64 da;
> > +
> > +     /* remap required addresses */
> > +     for (a = 0; a < dcfg->att_size; a++) {
> > +             const struct imx_dsp_rproc_att *att = &dcfg->att[a];
> > +
> > +             if (!(att->flags & ATT_OWN))
> > +                     continue;
> > +
> > +             if (imx_dsp_rproc_sys_to_da(priv, att->sa, att->size, &da))
> > +                     return -EINVAL;
> > +
> > +             cpu_addr = devm_ioremap_wc(dev, att->sa, att->size);
> > +
> > +             /* Register memory region */
> > +             mem = rproc_mem_entry_init(dev, cpu_addr, (dma_addr_t)att->sa,
> > +                                        att->size, da,
> > +                                        NULL,
> > +                                        NULL,
> > +                                        "dsp_mem");
> > +
> > +             if (mem)
> > +                     rproc_coredump_add_segment(rproc, da, att->size);
> > +             else
> > +                     return -ENOMEM;
> > +
> > +             rproc_add_carveout(rproc, mem);
> > +     }
> > +
> > +     of_phandle_iterator_init(&it, np, "memory-region", NULL, 0);
> > +     while (of_phandle_iterator_next(&it) == 0) {
> > +             /*
> > +              * Ignore the first memory region which will be used vdev buffer.
> > +              * No need to do extra handlings, rproc_add_virtio_dev will handle it.
> > +              */
> > +             if (!strcmp(it.node->name, "vdev0buffer"))
> > +                     continue;
> > +
> > +             rmem = of_reserved_mem_lookup(it.node);
> > +             if (!rmem) {
> > +                     dev_err(dev, "unable to acquire memory-region\n");
> > +                     return -EINVAL;
> > +             }
> > +
> > +             if (imx_dsp_rproc_sys_to_da(priv, rmem->base, rmem->size, &da))
> > +                     return -EINVAL;
> > +
> > +             cpu_addr = devm_ioremap_wc(dev, rmem->base, rmem->size);
> > +
> > +             /* Register memory region */
> > +             mem = rproc_mem_entry_init(dev, cpu_addr, (dma_addr_t)rmem->base,
> > +                                        rmem->size, da,
> > +                                        NULL,
> > +                                        NULL,
> > +                                        it.node->name);
> > +
> > +             if (mem)
> > +                     rproc_coredump_add_segment(rproc, da, rmem->size);
> > +             else
> > +                     return -ENOMEM;
> > +
> > +             rproc_add_carveout(rproc, mem);
> > +     }
> > +
> > +     return 0;
> > +}
> > +
> > +/*
> > + * imx_dsp_rproc_elf_load_segments() specially check if memsz is zero
> > + * or not.
> > + */
> > +static int imx_dsp_rproc_elf_load_segments(struct rproc *rproc,
> > +                                        const struct firmware *fw)
> > +{
> > +     struct device *dev = &rproc->dev;
> > +     u8 class = fw_elf_get_class(fw);
> > +     u32 elf_phdr_get_size = elf_size_of_phdr(class);
> > +     const u8 *elf_data = fw->data;
> > +     const void *ehdr, *phdr;
> > +     int i, ret = 0;
> > +     u16 phnum;
> > +
> > +     ehdr = elf_data;
> > +     phnum = elf_hdr_get_e_phnum(class, ehdr);
> > +     phdr = elf_data + elf_hdr_get_e_phoff(class, ehdr);
> > +
> > +     /* go through the available ELF segments */
> > +     for (i = 0; i < phnum; i++, phdr += elf_phdr_get_size) {
> > +             u64 da = elf_phdr_get_p_paddr(class, phdr);
> > +             u64 memsz = elf_phdr_get_p_memsz(class, phdr);
> > +             u64 filesz = elf_phdr_get_p_filesz(class, phdr);
> > +             u64 offset = elf_phdr_get_p_offset(class, phdr);
> > +             u32 type = elf_phdr_get_p_type(class, phdr);
> > +             void *ptr;
> > +             bool is_iomem;
> > +
> > +             if (type != PT_LOAD || !memsz)
> > +                     continue;
> > +
> > +             dev_dbg(dev, "phdr: type %d da 0x%llx memsz 0x%llx filesz 0x%llx\n",
> > +                     type, da, memsz, filesz);
> > +
> > +             if (filesz > memsz) {
> > +                     dev_err(dev, "bad phdr filesz 0x%llx memsz 0x%llx\n",
> > +                             filesz, memsz);
> > +                     ret = -EINVAL;
> > +                     break;
> > +             }
> > +
> > +             if (offset + filesz > fw->size) {
> > +                     dev_err(dev, "truncated fw: need 0x%llx avail 0x%zx\n",
> > +                             offset + filesz, fw->size);
> > +                     ret = -EINVAL;
> > +                     break;
> > +             }
> > +
> > +             if (!rproc_u64_fit_in_size_t(memsz)) {
> > +                     dev_err(dev, "size (%llx) does not fit in size_t type\n",
> > +                             memsz);
> > +                     ret = -EOVERFLOW;
> > +                     break;
> > +             }
> > +
> > +             /* grab the kernel address for this device address */
> > +             ptr = rproc_da_to_va(rproc, da, memsz, &is_iomem);
> > +             if (!ptr) {
> > +                     dev_err(dev, "bad phdr da 0x%llx mem 0x%llx\n", da,
> > +                             memsz);
> > +                     ret = -EINVAL;
> > +                     break;
> > +             }
> > +
> > +             /* put the segment where the remote processor expects it */
> > +             if (filesz)
> > +                     memcpy(ptr, elf_data + offset, filesz);
> > +
> > +             /*
> > +              * Zero out remaining memory for this segment.
> > +              *
> > +              * This isn't strictly required since dma_alloc_coherent already
> > +              * did this for us. albeit harmless, we may consider removing
> > +              * this.
> > +              */
> > +             if (memsz > filesz)
> > +                     memset(ptr + filesz, 0, memsz - filesz);
> > +     }
> > +
> > +     return ret;
> > +}
> > +
> > +static int imx_dsp_rproc_prepare(struct rproc *rproc)
> > +{
> > +     struct imx_dsp_rproc *priv = rproc->priv;
> > +     struct device *dev = priv->dev;
> > +     struct rproc_mem_entry *carveout;
> > +     int ret;
> > +
> > +     ret = imx_dsp_rproc_add_carveout(priv);
> > +     if (ret) {
> > +             dev_err(dev, "failed on imx_dsp_rproc_add_carveout\n");
> > +             return ret;
> > +     }
> > +
> > +     pm_runtime_get_sync(dev);
> > +
> > +     /* clear buffers */
> > +     list_for_each_entry(carveout, &rproc->carveouts, node) {
> > +             if (carveout->va)
> > +                     memset(carveout->va, 0, carveout->len);
> > +     }
> > +
> > +     return  0;
> > +}
> > +
> > +static int imx_dsp_rproc_unprepare(struct rproc *rproc)
> > +{
> > +     struct imx_dsp_rproc *priv = rproc->priv;
> > +
> > +     pm_runtime_put_sync(priv->dev);
> > +
> > +     return  0;
> > +}
> > +
> > +static void imx_dsp_rproc_kick(struct rproc *rproc, int vqid)
> > +{
> > +     struct imx_dsp_rproc *priv = rproc->priv;
> > +     int err;
> > +     __u32 mmsg;
> > +
> > +     if (!priv->tx_ch) {
> > +             dev_err(priv->dev, "No initialized mbox tx channel\n");
> > +             return;
> > +     }
> > +
> > +     /*
> > +      * Send the index of the triggered virtqueue as the mu payload.
> > +      * Let remote processor know which virtqueue is used.
> > +      */
> > +     mmsg = vqid;
> > +
> > +     err = mbox_send_message(priv->tx_ch, (void *)&mmsg);
> > +     if (err < 0)
> > +             dev_err(priv->dev, "%s: failed (%d, err:%d)\n",
> > +                     __func__, vqid, err);
> > +}
> > +
> > +static const struct rproc_ops imx_dsp_rproc_ops = {
> > +     .prepare        = imx_dsp_rproc_prepare,
> > +     .unprepare      = imx_dsp_rproc_unprepare,
> > +     .start          = imx_dsp_rproc_start,
> > +     .stop           = imx_dsp_rproc_stop,
> > +     .kick           = imx_dsp_rproc_kick,
> > +     .load           = imx_dsp_rproc_elf_load_segments,
> > +     .parse_fw       = rproc_elf_load_rsc_table,
> > +     .sanity_check   = rproc_elf_sanity_check,
> > +     .get_boot_addr  = rproc_elf_get_boot_addr,
> > +};
> > +
> > +static int imx_dsp_attach_pm_domains(struct imx_dsp_rproc *priv)
> > +{
> > +     struct device *dev = priv->dev;
> > +     int ret, i;
> > +
> > +     priv->num_domains = of_count_phandle_with_args(dev->of_node,
> > +                                                    "power-domains",
> > +                                                    "#power-domain-cells");
> > +     if (priv->num_domains <= 1)
> > +             return 0;
> > +
> > +     priv->pd_dev = devm_kmalloc_array(dev, priv->num_domains,
> > +                                       sizeof(*priv->pd_dev),
> > +                                       GFP_KERNEL);
> > +     if (!priv->pd_dev)
> > +             return -ENOMEM;
> > +
> > +     priv->pd_dev_link = devm_kmalloc_array(dev, priv->num_domains,
> > +                                            sizeof(*priv->pd_dev_link),
> > +                                            GFP_KERNEL);
> > +     if (!priv->pd_dev_link)
> > +             return -ENOMEM;
> > +
> > +     for (i = 0; i < priv->num_domains; i++) {
> > +             priv->pd_dev[i] = dev_pm_domain_attach_by_id(dev, i);
> > +             if (IS_ERR(priv->pd_dev[i]))
> > +                     return PTR_ERR(priv->pd_dev[i]);
> > +
> > +             priv->pd_dev_link[i] = device_link_add(dev,
> > +                                                    priv->pd_dev[i],
> > +                                                    DL_FLAG_STATELESS |
> > +                                                    DL_FLAG_PM_RUNTIME |
> > +                                                    DL_FLAG_RPM_ACTIVE);
> > +             if (IS_ERR(priv->pd_dev_link[i])) {
> > +                     dev_pm_domain_detach(priv->pd_dev[i], false);
> > +                     ret = PTR_ERR(priv->pd_dev_link[i]);
> > +                     goto detach_pm;
> > +             }
> > +     }
> > +
> > +     return 0;
> > +
> > +detach_pm:
> > +     while (--i >= 0) {
> > +             device_link_del(priv->pd_dev_link[i]);
> > +             dev_pm_domain_detach(priv->pd_dev[i], false);
> > +     }
> > +
> > +     return ret;
> > +}
> > +
> > +static int imx_dsp_detach_pm_domains(struct imx_dsp_rproc *priv)
> > +{
> > +     int i;
> > +
> > +     if (priv->num_domains <= 1)
> > +             return 0;
> > +
> > +     for (i = 0; i < priv->num_domains; i++) {
> > +             device_link_del(priv->pd_dev_link[i]);
> > +             dev_pm_domain_detach(priv->pd_dev[i], false);
> > +     }
> > +
> > +     return 0;
> > +}
> > +
> > +static int imx_dsp_rproc_detect_mode(struct imx_dsp_rproc *priv)
> > +{
> > +     const struct imx_dsp_rproc_dcfg *dcfg = priv->dcfg;
> > +     struct device *dev = priv->dev;
> > +     struct regmap *regmap;
> > +     int ret = 0;
> > +
> > +     switch (dcfg->method) {
> > +     case IMX_DSP_SCU_API:
> > +             ret = imx_scu_get_handle(&priv->ipc_handle);
> > +             if (ret)
> > +                     return ret;
> > +             return 0;
> > +     case IMX_DSP_MMIO:
> > +             regmap = syscon_regmap_lookup_by_phandle(dev->of_node, "fsl,dsp-ctrl");
> > +             if (IS_ERR(regmap)) {
> > +                     dev_err(dev, "failed to find syscon\n");
> > +                     return PTR_ERR(regmap);
> > +             }
> > +
> > +             priv->regmap = regmap;
> > +     default:
> > +             break;
> > +     }
> > +
> > +     return ret;
> > +}
> > +
> > +static const char *imx_dsp_clks_names[DSP_RPROC_CLK_MAX] = {
> > +     /* DSP clocks */
> > +     "dsp_clk1", "dsp_clk2", "dsp_clk3", "dsp_clk4", "dsp_clk5", "dsp_clk6",
> > +     "dsp_clk7", "dsp_clk8",
> > +
> > +     /* Peripheral clocks */
> > +     "per_clk1", "per_clk2", "per_clk3", "per_clk4", "per_clk5", "per_clk6",
> > +     "per_clk7", "per_clk8", "per_clk9", "per_clk10", "per_clk11", "per_clk12",
> > +     "per_clk13", "per_clk14", "per_clk15", "per_clk16", "per_clk17", "per_clk18",
> > +};
> > +
> > +static int imx_dsp_rproc_clk_get(struct imx_dsp_rproc *priv)
> > +{
> > +     int i;
> > +
> > +     for (i = 0; i < DSP_RPROC_CLK_MAX; i++) {
> > +             priv->clks[i] = devm_clk_get_optional(priv->dev,
> > +                                                   imx_dsp_clks_names[i]);
> > +             if (IS_ERR(priv->clks[i])) {
> > +                     dev_err(priv->dev, "Failed to get clock %s\n",
> > +                             imx_dsp_clks_names[i]);
> > +                     return PTR_ERR(priv->clks[i]);
> > +             }
> > +     }
> > +
> > +     return 0;
> > +}
> > +
> > +static int imx_dsp_rproc_clk_enable(struct imx_dsp_rproc *priv)
> > +{
> > +     int i, ret;
> > +
> > +     for (i = 0; i < DSP_RPROC_CLK_MAX; i++) {
> > +             ret = clk_prepare_enable(priv->clks[i]);
> > +             if (ret < 0) {
> > +                     dev_err(priv->dev, "Failed to enable clk %s\n",
> > +                             imx_dsp_clks_names[i]);
> > +                     goto err_dsp_clks;
> > +             }
> > +     }
> > +
> > +     return 0;
> > +
> > +err_dsp_clks:
> > +     while (--i >= 0)
> > +             clk_disable_unprepare(priv->clks[i]);
> > +
> > +     return ret;
> > +}
> > +
> > +static void imx_dsp_rproc_clk_disable(struct imx_dsp_rproc *priv)
> > +{
> > +     int i;
> > +
> > +     for (i = 0; i < DSP_RPROC_CLK_MAX; i++)
> > +             clk_disable_unprepare(priv->clks[i]);
> > +}
> > +
> > +static int imx_dsp_rproc_probe(struct platform_device *pdev)
> > +{
> > +     struct device *dev = &pdev->dev;
> > +     const struct imx_dsp_rproc_dcfg *dcfg;
> > +     struct imx_dsp_rproc *priv;
> > +     struct rproc *rproc;
> > +     const char *fw_name;
> > +     int ret;
> > +
> > +     dcfg = of_device_get_match_data(dev);
> > +     if (!dcfg)
> > +             return -ENODEV;
> > +
> > +     ret = rproc_of_parse_firmware(dev, 0, &fw_name);
> > +     if (ret) {
> > +             dev_err(dev, "failed to parse firmware-name property, ret = %d\n",
> > +                     ret);
> > +             return ret;
> > +     }
> > +
> > +     rproc = rproc_alloc(dev, "imx-dsp-rproc", &imx_dsp_rproc_ops, fw_name,
> > +                         sizeof(*priv));
> > +     if (!rproc)
> > +             return -ENOMEM;
> > +
> > +     priv = rproc->priv;
> > +     priv->rproc = rproc;
> > +     priv->dcfg = dcfg;
> > +     priv->dev = dev;
> > +
> > +     dev_set_drvdata(dev, rproc);
> > +
> > +     priv->workqueue = create_workqueue(dev_name(dev));
> > +     if (!priv->workqueue) {
> > +             dev_err(dev, "cannot create workqueue\n");
> > +             ret = -ENOMEM;
> > +             goto err_wkq;
> > +     }
> > +
> > +     INIT_WORK(&priv->rproc_work, imx_dsp_rproc_vq_work);
> > +
> > +     ret = imx_dsp_rproc_detect_mode(priv);
> > +     if (ret) {
> > +             dev_err(dev, "failed on imx_dsp_rproc_detect_mode\n");
> > +             goto err_detect;
> > +     }
> > +
> > +     ret = imx_dsp_attach_pm_domains(priv);
> > +     if (ret) {
> > +             dev_err(dev, "failed on imx_dsp_attach_pm_domains\n");
> > +             goto err_pm;
> > +     }
> > +
> > +     ret = imx_dsp_rproc_clk_get(priv);
> > +     if (ret) {
> > +             dev_err(dev, "failed on imx_dsp_rproc_clk_get\n");
> > +             goto err_clk_get;
> > +     }
> > +
> > +     init_completion(&priv->pm_comp);
> > +     rproc->auto_boot = false;
> > +     ret = rproc_add(rproc);
> > +     if (ret) {
> > +             dev_err(dev, "rproc_add failed\n");
> > +             goto err_rproc_add;
> > +     }
> > +
> > +     pm_runtime_enable(dev);
> > +
> > +     return 0;
> > +
> > +err_rproc_add:
> > +err_clk_get:
> > +     imx_dsp_detach_pm_domains(priv);
> > +err_pm:
> > +err_detect:
> > +     destroy_workqueue(priv->workqueue);
> > +err_wkq:
> > +     rproc_free(rproc);
> > +
> > +     return ret;
> > +}
> > +
> > +static int imx_dsp_rproc_remove(struct platform_device *pdev)
> > +{
> > +     struct rproc *rproc = platform_get_drvdata(pdev);
> > +     struct imx_dsp_rproc *priv = rproc->priv;
> > +
> > +     pm_runtime_disable(&pdev->dev);
> > +     rproc_del(rproc);
> > +     imx_dsp_detach_pm_domains(priv);
> > +     destroy_workqueue(priv->workqueue);
> > +     rproc_free(rproc);
> > +
> > +     return 0;
> > +}
> > +
> > +/* pm runtime */
> > +static int imx_dsp_runtime_resume(struct device *dev)
> > +{
> > +     struct rproc *rproc = dev_get_drvdata(dev);
> > +     struct imx_dsp_rproc *priv = rproc->priv;
> > +     const struct imx_dsp_rproc_dcfg *dcfg = priv->dcfg;
> > +     int ret;
> > +
> > +     ret = imx_dsp_rproc_mbox_init(priv);
> > +     if (ret) {
> > +             dev_err(dev, "failed on imx_dsp_rproc_mbox_init\n");
> > +             return ret;
> > +     }
> > +
> > +     ret = imx_dsp_rproc_clk_enable(priv);
> > +     if (ret) {
> > +             dev_err(dev, "failed on imx_dsp_rproc_clk_enable\n");
> > +             return ret;
> > +     }
> > +
> > +     /* reset DSP if needed */
> > +     if (dcfg->reset)
> > +             dcfg->reset(priv);
> > +
> > +     return 0;
> > +}
> > +
> > +static int imx_dsp_runtime_suspend(struct device *dev)
> > +{
> > +     struct rproc *rproc = dev_get_drvdata(dev);
> > +     struct imx_dsp_rproc *priv = rproc->priv;
> > +
> > +     imx_dsp_rproc_clk_disable(priv);
> > +
> > +     imx_dsp_rproc_free_mbox(priv);
> > +
> > +     return 0;
> > +}
> > +
> > +static void imx_dsp_load_firmware(const struct firmware *fw, void *context)
> > +{
> > +     struct rproc *rproc = context;
> > +     int ret;
> > +
> > +     /* load the ELF segments to memory */
> > +     ret = rproc_load_segments(rproc, fw);
> > +     if (ret)
> > +             goto out;
> > +
> > +     /* power up the remote processor */
> > +     ret = rproc->ops->start(rproc);
> > +     if (ret)
> > +             goto out;
> > +
> > +     /* same flow as first start */
> > +     rproc->ops->kick(rproc, 0);
> > +
> > +out:
> > +     release_firmware(fw);
> > +}
> > +
> > +static int imx_dsp_suspend(struct device *dev)
> > +{
> > +     struct rproc *rproc = dev_get_drvdata(dev);
> > +     struct imx_dsp_rproc *priv = rproc->priv;
> > +     __u32 mmsg = RP_MBOX_SUSPEND_SYSTEM;
> > +     int ret;
> > +
> > +     if (rproc->state == RPROC_RUNNING) {
>
>         if (rproc->state != RPROC_RUNNING)
>                 return;

All right,  I will update it.

>
> > +             reinit_completion(&priv->pm_comp);
> > +
> > +             ret = mbox_send_message(priv->tx_ch, (void *)&mmsg);
> > +             if (ret < 0) {
> > +                     dev_err(dev, "PM mbox_send_message failed: %d\n", ret);
> > +                     return ret;
> > +             }
> > +
> > +             if (!wait_for_completion_timeout(&priv->pm_comp, msecs_to_jiffies(100)))
> > +                     return -EBUSY;
> > +     }
> > +
> > +     return pm_runtime_force_suspend(dev);
>
> Please add a comment that explains why this needs to be called.

Ok.

>
> > +}
> > +
> > +static int imx_dsp_resume(struct device *dev)
> > +{
> > +     struct rproc *rproc = dev_get_drvdata(dev);
> > +     int ret = 0;
> > +
> > +     ret = pm_runtime_force_resume(dev);
> > +     if (ret)
> > +             return ret;
> > +
> > +     if (rproc->state == RPROC_RUNNING) {
>
> Same as above
>
> > +             /*TODO: load firmware and start */
>
> Not sure about the "TODO" part... To me this is exactly what
> request_firmware_nowait() does.

Sorry, this should be refined.

>
> > +             ret = request_firmware_nowait(THIS_MODULE,
> > +                                           FW_ACTION_UEVENT,
> > +                                           rproc->firmware,
> > +                                           dev,
> > +                                           GFP_KERNEL,
> > +                                           rproc,
> > +                                           imx_dsp_load_firmware);
>
> Stacking.

I will update it.

>
> Based on the implementation of imx_dsp_load_firmare() I have to guess that image
> segments are lost during a system suspend, which requires re-loading upon system
> resume.

Right.

>
> Once again,I have to guess because there is no comments in the code.  Look
> at what the TI guys have done in omap_remoteproc.c.  Even when I look at their
> code for the first time I clearly understand what the driver does, and that
> without any knowledge about the HW.
>
> I will stop here for this patchset.

Thanks.  I will add more comments.

>
> Thanks,
> Mathieu
>
> > +             if (ret < 0) {
> > +                     dev_err(dev, "load firmware failed: %d\n", ret);
> > +                     goto err;
> > +             }
> > +     }
> > +
> > +     return 0;
> > +
> > +err:
> > +     pm_runtime_force_suspend(dev);
> > +
> > +     return ret;
> > +}
> > +
> > +static const struct dev_pm_ops imx_dsp_rproc_pm_ops = {
> > +     SET_SYSTEM_SLEEP_PM_OPS(imx_dsp_suspend, imx_dsp_resume)
> > +     SET_RUNTIME_PM_OPS(imx_dsp_runtime_suspend,
> > +                        imx_dsp_runtime_resume, NULL)
> > +};
> > +
> > +static const struct of_device_id imx_dsp_rproc_of_match[] = {
> > +     { .compatible = "fsl,imx8qxp-hifi4", .data = &imx_dsp_rproc_cfg_imx8qxp },
> > +     { .compatible = "fsl,imx8qm-hifi4",  .data = &imx_dsp_rproc_cfg_imx8qm },
> > +     { .compatible = "fsl,imx8mp-hifi4",  .data = &imx_dsp_rproc_cfg_imx8mp },
> > +     { .compatible = "fsl,imx8ulp-hifi4", .data = &imx_dsp_rproc_cfg_imx8ulp },
> > +     {},
> > +};
> > +MODULE_DEVICE_TABLE(of, imx_dsp_rproc_of_match);
> > +
> > +static struct platform_driver imx_dsp_rproc_driver = {
> > +     .probe = imx_dsp_rproc_probe,
> > +     .remove = imx_dsp_rproc_remove,
> > +     .driver = {
> > +             .name = "imx-dsp-rproc",
> > +             .of_match_table = imx_dsp_rproc_of_match,
> > +             .pm = &imx_dsp_rproc_pm_ops,
> > +     },
> > +};
> > +module_platform_driver(imx_dsp_rproc_driver);
> > +
> > +MODULE_LICENSE("GPL v2");
> > +MODULE_DESCRIPTION("i.MX HiFi Core Remote Processor Control Driver");
> > +MODULE_AUTHOR("Shengjiu Wang <shengjiu.wang@nxp.com>");
> > --
> > 2.17.1
> >